In working on this slideshow, I was amazed how the Samsung Galaxy S4 smartphone, for this one brief moment, is really influential and a good example of these trends: it has humidity and temperature sensors, IR sensors for gesture recognition, ambient light sensors, the usual sensors that make the camera work, pressure (barometer), accelerometers -- all i need is my fuel cell sensor so the phone can be its own breathalyzer. If you get a chance, take a look at iFixit's teardown photos here. It's a pretty amazing piece of engineering.